it certainly does sound like a mini blockage. At least it passed pretty quickly for you.
One of the issues contributing to the leakage because of the diarrhoea may be because in hospital you are spending most of your time lieing down and not upright. When you're upright most of the day, the stool, hopefully, will slip down into the bag and not have to find its way out via the wafer like it does when you're lieing down.
This isn't to say you won't experience leaks once you're up and around. You most probably will, especially at first - most new ostomates do, but once you find the right appliance type for you (you DON'T have to stay with what they give you in hospital - ring around the different manufacturers and ask for free samples to try out), leaks should be few and far between.
NOTE: your stool after an ileostomy will never be more than 'toothpaste' like consistency. At first it will be more watery than normal anyway until your bowel settles down. After a while, your small bowel will realise it has to do the job of the large bowel and absorb a little more water, although it will never be as effective as the large bowel was. Give it time and it will thicken up a little.
I'm not a complete idiot - some parts are missing!
Ileostomy for 29 years since I was 10 years old, due to UC.